Various immunosuppressants are currently used in order to suppress rejections and other transplantation immunity reactions that may occur in organ transplantation, and among such suppressive agents are steroid hormones, antimetabolites, alkylating agents and antibiotics. Steroid hormones are effective against a wide variety of allergic diseases, whereas non-steroidal anti-inflammatory agents and anti-inflammatory enzymes are commonly used in symptomatic therapy of inflammations that accompany allergic reactions. Gold compounds and chloroquines are used expressly against rheumatoid arthritis. For the treatment of bronchial asthma and unticaria, anti-histamine ae used.
Existing immunosuppressants generally cause serious side effects when they are administered to humans. It is therefore desired to develop immunosuppressive drugs that act selectively on lymphocytes and other cells of immdnological importance while causing minimum side effects.
On the other hand, in order to cope with the increasing incidence of allergic diseases such as allergic asthma, allergic rhinitis and pollinoala, the development of effective antiallergic agents is desired.
Spergualin is a compound that was isolated by Umezawa, one of the inventors of the present invention, and other from the filtrate of a culture broth of Spergualin-producing microorganism of the genus Bacillus (see Japanese Patent Public Disclosure No. 48957/1982).